1. Field of the Invention
The present invention relates to a manufacturing method of an imaging module, an imaging module and an electronic device having the imaging module.
2. Description of the Related Art
A small and thin imaging module is mounted on a portable electronic device such as a portable phone having a photographing function. The imaging module has a structure in which a lens unit, into which a photographic lens is incorporated, and an imaging element unit into which an imaging element such as a CCD image sensor, a CMOS image sensor, or the like is incorporated are integrated with each other.
As the imaging module, there is an imaging module which has an auto focus (AF) mechanism which moves a lens in the lens unit for performing focus adjustment, and an imaging module which has an optical type image blur correction mechanism which relatively moves the lens unit and the imaging element unit in a direction orthogonal to an optical axis for optically correcting blur of a captured image.
For example, JP2010-21985A and JP2010-88088A disclose the imaging module having the AF mechanism, and JP2011-247909A discloses the imaging module having the AF mechanism and the optical type image blur correction mechanism.
In recent years, instead of an imaging element having a low pixel number such as approximately one million pixels to two million pixels, an imaging element having a high pixel number such as three million pixels to ten million pixels or more is widely used in the imaging module.
When the imaging element of a low pixel number is used, particularly, high accuracy is not required for positioning of the lens unit and the imaging element unit. However, when the imaging element having a high pixel number is used, high accuracy is required for the positioning.
In JP2010-21985A and JP2010-88088A, a technology is disclosed in which positioning of a lens unit and an imaging element unit and fixation between the lens unit and the imaging element unit are automatically performed.
In this technology, after the lens unit and the imaging element unit are set to an initial position, a measurement chart is captured by the imaging element while the imaging element unit moves in an optical axis direction, and the positions of the lens unit and the imaging element unit are adjusted from the obtained captured image. After the adjustment, the lens unit and the imaging element unit are bonded and fixed to each other.